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The formulation of quarkyonic matter consists of treating both quarks and nucleons as quasi-particles, where a cross-over transition occurs between the two phases. This work is based upon some of the early ideas of quark matter. It can satisfy the different observational constraints on the neutron star (NS), such as its maximum mass and the canonical radius. In addition, we put an extra component inside the NS known as Dark Matter (DM) because it is trapped due to its immense gravitational potential. In this work, we explore the impact of fermionic DM on the structure of the NS. The equation of state (EOS) is derived for the NS with the quarkyonic matter by assuming that nucleons and quarks are in equilibrium, followed by the relativistic mean-field (RMF) formalism. The recently modeled two parameterizations, such as G3 and IOPB-I, are taken to calculate the various macroscopic properties of the NS. The three unknown parameters such as the transition density ($n_t$), the QCD confinement scale ($\Lambda_{\rm sc}$), and the DM Fermi momentum ($k_f^{\rm DM}$) are varied to obtain the NS properties. The quarkyonic matter stiffens the EOS while DM softens it. The mutual combination provides us with good theoretical predictions for the magnitude of macroscopic properties consistent with the different observational results. Also, one can estimate the parameters of the DM admixed quarkyonic star with different statistical analyses, which can be further used to explore the other properties of the quarkyonic star., Comment: 23 pages, 7 figures and 4 tables

Spontaneous magnetic order is a routine instance in three-dimensional (3D) materials but for a long time, it remained elusive in the 2D world. Recently, the first examples of (stand-alone) 2D van der Waals (vdW) crystals with magnetic order, either antiferromagnetic or ferromagnetic, have been reported. In this review, we describe the state of the art of the nascent field of magnetic 2D materials focusing on synthesis, engineering, and theory aspects. We also discuss challenges and some of the many different promising directions for future work.

A large 4$\pi$ array of charged particle detectors has been developed at Variable Energy Cyclotron Centre to facilitate high resolution charged particle reaction and spectroscopy studies by detecting event-by-event the charged reaction products emitted in heavy ion reactions at energy $\sim$ 10-60 MeV/A. The forward part ($\theta \sim \pm $ $7^{0}$ - $\pm 45^{0}$) of the array consists of 24 highly granular, high resolution charged particle telescopes, each of which is made by three layers [single sided silicon strip($\Delta$E) + double sided silicon strip (E/$\Delta$E) + CsI(Tl)(E)]of detectors. The backward part of the array consists of 112 CsI(Tl) detectors which are capable of detecting primarily the light charged particles (Z $\le$ 2) emitted in the angular range of $\theta \sim \pm $ $45^{0}$ - $\pm 175^{0}$. The extreme forward part of the array ($\theta \sim \pm $ $3^{0}$ - $\pm 7^{0}$) is made up of 32 slow-fast plastic phoswich detectors that are capable of detecting light (Z $\le$2) and heavy charged particles (3 $\le$ Z $\lesssim$ 20) as well as handling high count rates. The design, construction and characterization of the array has been described., Comment: Paper has been submitted in NIMA

In the present communication we report the preparation and characterizations of Langmuir and Langmuir-Blodgett films of a thiacyanine dye-dioctadecyl thiacyanine perchlorate (NK) mixed with Octadecyl trimethyl ammonium bromide (OTAB). The relationship between the molar ratio of OTAB and NK and the orientation of molecules at the air-water interface was investigated using surface pressure - area per molecule ({\pi}-A) isotherm. UV-Vis absorption and fluorescence spectroscopic investigations reveal that prominent J-aggregation of NK molecule was observed in the LB films lifted at higher surface pressure. This J-aggregation can be controlled by diluting the NK molecules with OTAB. It was observed that the J-aggregates of NK decayed to monomer and H-aggregates when the NK-LB film was exposed to a monochromatic light of wavelength 460 nm (Lambda max of J - aggregates)., Comment: 12 pages, 5 figures, 1 table

This communication reports the formation and characterization of self assembled films of a low molecular weight anionic dye amaranth and polycation Poly (allylamine hydrochloride) (PAH) by electrostatic alternating Layer-by-Layer (LBL) adsorption. It was observed that there was almost no material loss occurred during adsorption process. The UV-Vis absorption and fluorescence spectra of amaranth solution reveal that with the increase in amaranth concentration in solution, the aggregated species starts to dominate over the monomeric species. New aggregated band at 600 nm was observed in amaranth-PAH mixture solution absorption spectrum. A new broad low intense band at the longer wavelength region, in the amaranth-PAH mixture solution fluorescence spectrum was observed due to the closer association of amaranth molecule while tagged into the polymer backbone of PAH and consequent formation of aggregates. The broad band system in the 650-750 nm region in the fluorescence spectra of different layered LBL films changes in intensity distribution among various bands within itself, with changing layer number and at 10 bilayer LBL films the longer wavelength band at 710 nm becomes prominent. Existence of dimeric or higher order n-meric species in the LBL films was confirmed by excitation spectroscopic studies. Almost 45 minute was required to complete the interaction between amaranth and PAH molecules in the 1-bilayer LBL film., Comment: 10 pages, 5 figures

Thin films based on Layer-by-Layer (LbL) self assembled technique are useful for immobilization of DNA onto solid support. This communication reports the immobilization of DNA onto a solid support by electrostatic interaction with a polycation Poly (allylamine hydrochloride) (PAH). UV-Vis absorption and steady state fluorescence spectroscopic studies exhibit the characteristics of DNA organized in LbL films. The most significant observation is that single strand DNA are immobilized on the PAH backbone of LbL films when the films are fabricated above the melting temperature of DNA. DNA immobilized in this way on LbL films remains as such when the temperature is restored at room temperature and the organization remains unaffected even after several days. UV-Vis absorption spectroscopic studies confirm this finding., Comment: Eight pages, five figures

A hierarchical structured control model was used to describe pilot performance in a multivariable control problem. The model is based on the assumption that a well trained operator optimized a quadratic optimization criterion. The model considers some special characteristics of the human operator as time delay, neuromuscular time lag, observation and motor noise and the ability to extract the first derivative of a displaced value. Numerical results of a simple human engineering example using the BBN model demonstrate the influence of the variation of different parameters on covariance matrices of the state and observation vectors.

The effect of a prediction display on the human transfer characteristics is explained with the aid of a quasi-linear model. The prediction display causes an increase of the gain factor and the lead factor, a diminishing of the lag factor and a decrease of the remnant. Altogether, these factors yield a smaller mean square value of the control deviation and a simultaneous decrease of the mean square value of the stick signal.